1. Field of the Invention
A heat exchanger assembly, and more specifically, an assembly including louvered fins.
2. Description of the Prior Art
Louvered air performance is critical to compact heat exchangers (such as radiator, heater, condenser, and evaporator) total heat transfer rate for automotive and STAC applications. A typical heat exchanger with a louvered air design includes a plurality of tubes extending parallel to one another and a fin extending back and forth between each pair of adjacent tubes. Typically, each fin defines at least one louvered portion having a plurality of louvers extending parallel to one another. The fin has legs extending between the tubes and a end portion interconnecting two adjacent legs to define an tube space.
Due to the manufacturing limitation, a typical height of the louvered portion is about 75%-85% of the total air center height, or total fin height. This manufacturing limitation has led to “un-louvered regions” in both end of the air center. In these two regions, the airflow is un-disrupted by the louver, airflow velocity is high, and the thermal boundary layers are thick.
US Application 2007/0012430 discloses an upper manifold extending along an upper centerline and a lower manifold extending along a lower centerline. The manifolds are spaced form one another with the centerlines being parallel to each other. The upper manifold defines a plurality of upper tube slots being spaced along the upper centerline. The lower manifold define a plurality of lower tube slots being spaced along the lower centerline and aligned with the upper tube slots.
A plurality of tubes have flat sides and extend between ends thereof in the upper and lower tube slots and are parallel and spaced from one another. A plurality of fins each extend back and forth between and along the flat sides of the adjacent ones of tubes forming a continuous serpentine path. Each of the fins include a plurality of legs that extend between the tubes and a plurality of end portions that extend along the tube sides adjacent ones of the tubes to define the serpentine path. The adjacent legs are connected by one of the end portions along one tube and are open to the opposite adjacent tube to define a tube space between the adjacent legs along the flat sides of the tubes.
Although the current assemblies are sufficient for their intended purposes, there remains a need for a louvered air center heat exchanger that improves heat transfer.